Cops and community leaders completely ignored city rules and put up an official-looking sign that names a Brooklyn bicycle lane for the NYPD Highway Patrol boss who killed himself amid a corruption probe, they admitted Wednesday.

A green-and-white sign declaring a stretch of Bergen Street in Prospect Heights the “Inspector Michael Ameri Bike Lane” was bolted in place by Public Advocate Letitia James and others Tuesday evening.

Eric McClure, president of the Park Slope Neighbors community group who also helped with the installation, admitted that the operation was done without official permission.

“It’s on the down-low,” he said. “I’d expect whoever is responsible for those things to turn a blind eye to it.

“I figured we’d go a little rogue.”

McClure hopes to eventually have the street renamed after Ameri.

City Councilman Brad Lander (D-Brooklyn), who also attended the ceremony, said: “What happened last night was an informal community tribute to a fallen friend. It was not a formal or ­official renaming.”

His suicide came a day after Internal Affairs Bureau investigators seized boxes of records from his Highway Division station house — weeks after he was interviewed by the feds as part of a probe into a suspected gifts-for-favors scheme involving official police escorts.

At the event for Ameri, there was no mention of the scandal.

Lander called him “a real friend, partner and mentor who made me better and taught me about service.”

“I miss him a lot. We’re gonna miss him a lot in the city and [are] paying a real tribute to him in the form of the sign, which I love,” Lander said.

“He brought the NYPD and this community together in a strong and powerful way.”

Under the City Charter, Transportation Commissioner Polly Trottenberg has authority over traffic signs “and similar devices indicating the names of the streets and other public places.”

A DOT spokesman said: “Any official, permanent bike-lane naming would have to go through the same legislative process as other street renamings.”

The sign was erected along the bike lane that Ameri established when he ran the 78th Precinct.